I just used the Galaxy Map trade routes. Found them no problem, and it was more up-to-date than EDDB. Most any military ground settlement will have them (usually they have "Arsenal" in their title).
I did find however, that the availability can go from a good stock to zero and back quickly. The base I bought my first load from had plenty in stock. I came back an hour later for a second load and there were none. I quit for the night and the next day they had a large stock again. Must be a bustling business?